Heretofore, there has been known a server virtualization technology in which a plurality of virtual servers so called as VMs (Virtual Machines) are running on a server serving as an information processing apparatus. On the server, a VMM (Virtual Machine Monitor) for executing various controls relating to the VMs, such as the creation of VMs, are running.
The above-mentioned server virtualization technology carries out live migration for transferring a VM which is running in a certain server onto another server without stopping the operation of the VM. Explanation will be made of an example of the process of this live migration with reference to FIGS. 22 and 23. FIG. 22 is a view illustrating the configuration of a system for carrying out the live migration, and FIG. 23 is a view illustrating an operation sequence of the live migration.
As depicted in FIG. 22, the above-mentioned example to be explained is such that a VM on server A which is a source server is transferred into server B which is a destination server. Further, VMMs for executing various controls relating to the VMs are running respectively on serves A and B. In this situation, as depicted in FIG. 23, the VMM which is running on server B as a destination server creates a new VM on server B in response to a command manipulation by the administrator.
Then, as depicted in FIG. 23, the VMM which is running on server A as a source server, executes pre-copy in the condition that the VM to be transferred is running in server A. Specifically, the VMM which is running on server A, transfers the content of a memory used by itself into the VMM on server B, and the VMM on server A repeats the pre-copy in accordance with a change amount in memory.
Thereafter, as depicted in FIG. 23, the VMM on server A executes stop-and-copy when the change amount in memory becomes not greater than a predetermined value. Specifically, the VMM in server A temporarily stops the work of the VM to be transferred, and transfers the content of the memory used by itself, into the VMM on server B.
Further, as depicted in FIG. 23, the VMM in server B initiates the VMM which has been transferred, in order to restart the work, and as well, transmits a reverse APP (Address Resolution Protocol) to a physical switch. Then, the VMM on server B notifies the fact that a MAC address (Media Access Control address) and an IP (Internet Protocol) address are transmitted to server B. By carrying out the live migration as described above, the VM may be transferred.
Patent Literature 1: Japanese Laid-open Patent Publication No. 2009-181418
Patent Literature 2: Japanese Laid-open Patent Publication No. 2009-217302
However, the prior art has raised a problem that an unnecessary traffic may possibly be generated when the migration is carried out.
For example, as depicted in the left side part of FIG. 24, an assumption is made such that a VM1 on a server A and a VM3 on a server B are connected together by a VLAN(A) which is one and the same VLAN (Virtual Local Area Network), and a VM2 on the server A and a VM4 on the server B are connected together by one and the same VLAN(B). In this case, the live migration is carried out for the VM2 from the server A onto the server B and for the VM3 from the server B onto the server A. The VLAN setting of external switches which constitute a network is executed, in the live-migration so that the server as a destination server also belongs to the VLAN. Accordingly, as depicted in the right side portion of FIG. 24, there is caused the condition that the VLANs the transferred VMs have used still remain on the respective servers, resulting in the generation of unnecessary traffics. FIG. 24 is a view illustrating a result of the live migration relating to the prior art.
The object and advantages of the embodiment will be realized and attained by means of the elements and combinations particularly pointed out in the claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the embodiment, as claimed.